1. Field of the Invention
The present invention generally relates to a flywheel assembly. More specifically, the present invention relates to a flywheel assembly including first and second flywheels coupled together by a damper mechanism.
2. Background Information
A flywheel is attached, for example, to a rear end of a crankshaft of an engine of a vehicle for preventing nonuniform rotation during low-speed driving by its moment of inertia. The flywheel carries a ring gear for a starter and a clutch.
Such a flywheel assembly has been known that a flywheel is divided into first and second flywheels, and a damper mechanism is arranged between them for elastically coupling the flywheels together in the rotating direction. The damper mechanism includes elastic members which are circumferentially compressed when the first and second flywheels rotate relatively to each other. A certain type of damper mechanism includes a friction generating mechanism which operates in parallel with the elastic members.
An engine produces a drive force by converting a combustion power into a rotational force through a crankshaft. The combustion power bends the crankshaft and vibrates the flywheel assembly in the bending direction. Thereby, a reaction force is transmitted from the flywheel assembly to an engine block, and is further transmitted to a body of a vehicle through an engine mount to vibrate the body. As a result, noises occur during acceleration of the engine. The second flywheel is likely to vibrate in the bending direction. This is because an inner periphery of the second flywheel is carried on a projection of the first flywheel through a bearing, and the bearing has a low degree of freedom in the bending direction.
In view of the above, there exists a need for a flywheel, which overcomes the above mentioned problems in the prior art. This invention addresses this need in the prior art as well as other needs, which will become apparent to those skilled in the art from this disclosure.